public static IReadOnlyList <Card> GetRandomCardDeck()
{
// choose 5 cards from pile of all cards
// shuffle five game cards because we've only randomly selected 5 but they are not shuffled.
var result = RandomExt.GetRandomChooseCombination(Card.AllCards, Card.AllCards.Count, 5);
result.Shuffle();
return(result.ToList());
}